Storage and feed means for a continuous web



March s, 1960 F. W. WALSH ETAL CONTINUOUS WEB of New York 13 Claims.(Cl. 2712.1)

such as a high speed automatic printing press.

tently or at variable rates.

the utilization device.

the first web accumulation.

embodiment of the invention.

STORAGE AND FEED MEANS FOR A Francis W. Walsh, Susquehanna, Pa., andHenry A. Hendrich, Endicott, N.Y., assignors to International BusinessMachines Corporation, New York, N .Y., a corporation Application January2, 1958, Serial N 0. 706,670

This invention relates to web feed means for use with a high speedmachine and more particularly to such apl. paratus in which the forcesacting on portions of the advancing web are utilized in the control ofthe storage and feed of the web as it is being fed to a high speedmachine In recognition of the necessity for coordinating the supply rateof a web to a utilization device in accordance with variations in thedemand rate of the utilization device, numerous arrangements havehitherto been proposed for controlling the feed of the web to theutilization device. Such arrangements with which I am familiar have leftmuch to be desired particularly due to the presence of undesirableinertial effects of parts operating intermit- A principal object of thepresent invention is, therefore, to provide a web feed and storageapparatus which is highly compact, in which the web is maintained undera substantially constant tension and characterized by substantialminimization or avoidance of inertial effects which would disturb thedesired constant web tension.

A feature of the present invention is the provision of low inertia meansfor applying a force to a web so that under the influence of said force,it is withdrawn from a source of web supply to maintain an accumulationof the web under a substantially uniform tension in advance of In apreferred embodiment suction means are utilized to create unequal forceson two longitudinally spaced portions of the web at each of which anaccumulation of t the web is normally maintained as it passes fromsupply means to the utilization device. The smaller force acts on theaccumulation of the first portion of the web and differential in theforces acting on the two accumulations results in the first accumulationbeing depleted before the second accumulation, the latter being nearerto the utilization device. When the utilization device with- .draws theWeb at a rate greater than the rate at which the smaller force acting onthe Web causes its withdrawal from the supply means, the firstaccumulation is depleted first. Means are provided for increasing therate of withdrawal from the supply means in response to depletion ofFurther advantages of the present invention will be apparent from thefollowing description thereof and the accompanying drawing, the singlefigure of which is a diagrammatic and schematic representation of apreferred In the drawing there is shown a web such as paper from asupply reel 12 being fed to a machine such as a ,printing press,represented by printing rolls 14, 16. To compensate for variationsbetween the speed of the Web leaving the supply roll and the speed ofthe web entering theprinting press, storage space is provided for asupply fof-paper atall times in a storage tank 18 between'the supplyroll and the press. In an embodiment that is especiallywell suitedforuse in connection with a high speed, automatic card printing press, thestorage tank isa rectangular box approximately 3% by 10 by 40 inches,and open at the top. The box is divided into two storage or accumulatorcompartments by a vertical partition 19 parallel to the greatestdimension of the tank. In the drawing the storage compartments aredesignated 20 and 22 respectively. The bottom of each of thecompartments 20, 22 is formed by perforated semi-cylindrical guides, 24and 26 respectively. The portion of the tank interior below the guides24, 26 is a vacuum compartment 28 which is connected by a conduit 30with a vacuum pump 32. The cross-sectional areas of the compartments 20,22 are made unequal, the compartment 22 being wider than the compartment20 so that the force exerted downward (as viewed) on the web by thevacuum in the compartment 22 is greater than that exerted in thecompartment 20, to facilitate control of the web as will appear morefully hereinbelow. In the embodiment hereinabove mentioned the ratio ofthe widths of the compartments is approximately three to two. At the topof the tank 18 are mounted a driven roll 34 and idler rolls 36, 38located respectively at the edge nearest the supply roll 12, at thepartition 19, and at the edge nearest the press. The web from the supplyroll 12 passes over the roll 34, loops down into the compartment 20 toform a first accumulation, passes over the idler roll 36, loops downinto the compartment 22 to form a second accumulation, passes over theidler roll 38, and thence to the press. Near the bottom of thecompartment 20, a lamp 40 is arranged to send a beam, as through a lensor window 42 in the wall of compartment 20 nearest the supply roll. Thebeam is arranged to impinge upon a photo-electric cell 44, which cell ispreferably embedded in the partition wall 19. When the loop 46 of theweb falls close to the bottom of compartment 20, the loop 46 interruptsthe light beam.

The loop 48 of web in the compartment 22 is intended at all times toextend entirely to the bottom of the compartment 22 where it is held inslidable contact with the perforated guide 26 by the force resultingfrom the pull of the vacuum which is, as hereinabove mentioned, greaterthan the force in the compartment 20, inasmuch as the same vacuum actsover a larger area of the web in compartment 22 than in compartment 20.Whenever the web is drawn into the press at a faster rate than it isleaving the supply roll, the greater force holds loop 48 down while theloop 46 rises upward in the compartment 20, uncovering the light beam ifthe loop is not already above the level of the beam. As will be morefully explained hereinbelow, the uncovering of the light beam resultingfrom depletion of the web accumulation in compartment 20 actuates amechanism for increasing the speed at which the web leaves the supplyreel.

The press is driven by motor 68 which, together with a retarded relay 74connected in series therewith, is connected in circuit with a suitablesource when start switch 69 is closed.

Normally when the press is started up into operation from a standstillthe web loops 46, 48 both are extended to the bottom of their respectivecompartments, providing in the embodiment hereinabove described areserve supply of about fourteen linear feet of paper. When the press isstarted it is permitted to accelerate to full speed without motorcontrol because the storage tank contains a suflic'ient supply of paperat an essentially uniform low tension suitable for feeding into thepress. This tension is governed by the pull of the vacuum upon the webloop 46 in compartment 20. It will be noted that in the event the rateat which paper is withdrawn by the press exceeds the rate of infeed fromsupply reel 12, then the differential in the forces acting on the loopsin compartments 20 and 22 results in the length of the loop incompartment 22 being maintained at the expense of the loop incompartment 20. Thus, the press in effect withdraws paper from theaccumulation in compartment 20 which is the compartment nearest thesupply reel.

A power-driven roll 50 is provided between the driven roll 34 and thesupply reel 12 and is driven as by an electric motor 52, which motor maybe designated the accelerator motor. Rotatably mounted above the roll 50is a pressure roll 54 which may be used to press the paper against thedriven roll 50 under the control of a solenoid A relay 58 connected inseries with photocell 44 and its source, battery 60, is provided forcontrolling, by means of its contacts 70, the supply of current to theaccelerator motor 52 from a suitable source. The accelerator means justdescribed functions during the start up cycle of the apparatus and isnot required during normal operation. To this end, contacts 79 and 71 ofrelay 58. are connected in series with the motor 52 and the solenoid 56,respectively. Normally closed contacts 75 of retarded relay 74 areconnected in series with the winding of relay 58 and in parallel withthe holding contacts 59] of relay 58. The delay of retarded relay 74 issufficiently long so that its contacts 75 remain closed followtheclosing of switch 69 for a time interval long enough for the press towithdraw web from compartment 2 and uncover the light beam from lamp 40.Photocell 44 now becomes conductive and relay 58 picks up its contacts59, 70 and 71. Now when relay 74 drops out at the .end of its delayperiod relay 58 remains energized through its holding contacts 59 solong as the photocell 44 is illuminated by the light beam from lamp 40,thereby keeping the circuits to accelerator motor 52 and solenoid 56closed. The accelerator means functions to bring the supply reel up tospeed with a somewhat slower rate of acceleration than the rate ofacceleration of the press. The initial operation of the press tends todeplete the accumulation in compartment 20 but the Web is rapidlyrestored in compartment 20 due to the operation of the accelerator.

A magnetic drag-brake 64 is located adjacent to the hub of reel 12, theenergization circuit of which is also {controlled by photocell 44 sowhen lamp 40 is uncovered and photocell 44 is energized, the brake 64 isreleased.

" During the start cycle, as soon as the light beam is uncovered by therise of the web loop, the electric circhit is established through thephoto-electric cell 44 and the battery 60 actuating the solenoid 56 andthe relay 58, thereby drawing the pressure roll 54 down upon the web andstarting the accelerator motor 52. At the same time magnetic brake 64 isreleased. The supply reel is then brought quickly up to a speed at whichit is capable of putting paper into the storage tank at a faster ratethan it is withdrawn by the press running at full speed. This causes theloop 46 to descend until it blocks the light beam thereby causing thepressure roll solenoid 56 to release, the accelerator motor 52 to beshut down and the magnetic brake 64 to retard rotation of supply reel12.

When the press is running normally, the paper is drawn from the supplyreel, rotation of which is now retarded by brake 64, by the action ofthe vacuum upon the loop 46. Stabilization is eifected by means of theroll 34 which is driven from motor 68 as is the press and at a speedwhich is faster than the demand speed of the press. In the embdoimentthat has been operated, the roll 34 is driven at about four percentabove the web demand speed of the press. The speed of the roll 34follows proportionately all speed variations of the press in every phaseof press operation. The web is maintained taut against the roll 34 bymeans of the vacuum in compartment 20. The web is continually in slidingengagement with the face of driven roll 34, the rate of revolution ofwhich is independent of the speed at which the web travels.Consequently, when the rate of travel of the web over roll 34 changes asbrake 64 .is successively energized and deenergized, the web is notaffected by the inertia of roll 34 as would be the case if roll 34 werean idler. Thus, the rail 34 acts as a dynamic stabilizer on the web.

The present apparatus is especially well suited for use with anautomatic splicer whereby the operation of the press is not interruptedwhen the supply reel is replenished due to the presence of theaccumulation of webin the tank 18. Such an automatic splicer splices theend of one reel of paper to the beginning of a new reel. This operationmay be made very rapid, requiring perhaps no more than one-tenth of asecond for its completion. During the splicing operation, the web fromthe reel is cut and stopped, during which time the press draws paperfrom the storage tank against the force resulting from the vacuumprovided by the air pressure means which includes vacuum pump 32. Uponcompletion of splicing, contacts, not shown, also in parallel withcontacts 59 of relay 58 are momentarily closed to complete theenergizing circuit of relay 58 which then closes its contacts 59 and 70and accelerator motor 52 is energized until the beam from lamp .40 isonce again blocked. The new reel is accelerated to full speed ashereinabove described and the storage tank is refilled in the samemanner as hereinabove described in connection with starting the press."The proportions of the storage tank may be varied within wide limitswhile still remaining within the scope of the invention. Also it will beevident that the invention is not limited to use with a. printing pressbut may be used in connection with other machines and processes whichoperate upon material in the form of a web. Materials other than papermay constitute the web, and other controls, such as hydraulic orpneumatic controls, may be used where electric or electronic controlsare shown.

The terms and expressions which have been employed are used as terms ofdescription and not of limitation, and there is no intention, in the useof such terms and expressions of excluding any equivalents of thefeatures shown and described or portions thereof, but it is recognizedthat various modifications are possible within the scope of theinvention claimed.

What is claimed is:

1. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming a compartment, meanscommunicating with said compartment for maintaining an air pressurediifer' ential across said web to thereby apply a force to said web andwithdraw it from the source thereof and maintain a web accumulation insaid compartment, control means responsive to the accumulation of web insaid compartment, and means governed by said control means for normallyretarding withdrawal of the web from its source while the web is movingunder the influence of said force from its source to said compartment,said control means in response to depletion of the accumulation of theweb causing said means governed thereby to reduce its retarding elfectupon the withdrawal of the web from its source.

2. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming a compartment, meanscommunicating with said compartment for maintaining an air pressuredifierential across said web to thereby apply a force to said web andwithdraw it from the source thereof and maintain a web accumulation insaid compartment, control means responsive to the accumulation of web insaid compartment, means governed by said control means for normallyretarding withdrawal of the web from its source while the web is movingunder the influence of said force from its source to said compartment,said control means in response to depletion of the accumulation of theweb causing said means governed thereby to reduce its retard: ing effectupon the withdrawal of the web from its source, and accelerating meansadapted to be energized u s se HR at t e util zetiaa d vi a acceleratingdf awalbf the web from its source, said control m eans upon restorationof the web accumulation being adapted to deenergize said acceleratormeans.

3. An apparatus as set forth in claim 2, comprising means for preventingreenergization of said accelerator means following deenergizationthereof by said control means during continued operation of saidutilization device.

4. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming a compartment, a roll on theinfeed side of said compartment, means for continuously rotating saidroll at a speed having a predetermined relation to the speed ofoperation of the utilization device, means com municating with saidcompartment for maintaining an air pressure differential across said webto thereby apply a force to said web and withdraw it from the sourcethereof and maintain a web accumulation in said compartment, said forcemaintaining said web taut against said roll, control means responsive tothe accumulation of web in said compartment, and means governed by saidcontrol means for normally retarding withdrawal of the moving web fromits source, said control means in response to depletion of theaccumulation of the web causing said means governed thereby to reduceits retarding effect upon the withdrawal of the web from its source.

5. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device having avariable web demand rate, first means for receiving a web on one sidethereof and accumulating a first portion of said web, second means onthe other side of said first means for receiving said web from saidfirst means and accumulating a second portion of said Web, said firstand second portions of said web being spaced in that sequencelongitudinally along the web in the direction it advances toward theutilization device, and means for maintaining a first and second forceon said first and second portions respectively of said web in adirection to oppose depletion of the web accumulations, said secondforce being greater than said first force,- said first force serving towithdraw the web from the source thereof, whereby on the occurrence ofan increase in the demand rate of said utilization device the firstaccumulated web portion is depleted before the start of depletion of thesecond accumulated web portion.

6. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device having avariable web demand rate, first means for receiving a web on one sidethereof and accumulating a first portion of said web, second means onthe other side of said first means for receiving said web from saidfirst means and accumulating a second portion of said web, said firstand second portions of said web being spaced in that sequencelongitudinally along the web in the direction it advances toward theutilization'device, and air pressure means for maintaining a first andsecond force on said first and second portions respectively of said webin a direction to oppose depletion of the Web accumulations, said secondforce being greater than said first force, said first force serving towithdraw the Web from the source thereof, whereby on the occurrence ofan increase in the demand rate of said utilization device the firstaccumulated web portion is depleted before the start of depletion of thesecond accumulated web portion.

7. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device having avariable web demand rate, first means for receiving a web on one sidethereof and accumulating a first portion of said web, second means onthe other side of said first means for receiving said web from saidfirst means and accumulating a second portion of said web, said firstand second portions of said web being spaced in that sequencelongitudinally along tion device, and means including a vacuum pumpcommunicating with said web portions for maintaining a first and secondforce on said first and second portions respectively of said web in adirection to oppose depletion of the web accumulations, said secondforce being greater than said first force, said first force serving towithdraw the web from the source thereof, whereby on the occurrence ofan increase in the demand rate of said utilization device the firstaccumulated web portion is depleted before the start of depletion of thesecond accumulated web portion.

8. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device having avariable web demand rate, first means for receiving a web on one sidethereof and accumulating a first portion of said web, second means onthe other side of said first means for receiving said web from saidfirst means and accumulating a second portion of said web, said firstand second portions of said web being spaced in that sequencelongitudinally along the Web in the direction it advances toward theutilization device, means including a vacuum pump communieating withsaid web portions for maintaining a first and second force on said firstand second portions respectively of said web in a direction to opposedepletion of the web accumulations, said second force being greater thansaid first force, said first force serving to withdraw the web from thesource thereof, whereby on the occurrence of an increase in the demandrate of said utilization device the first accumulated web portion isdepleted before the start of depletion of the second accumulated webportion, control means responsive to said first accumulated portion ofsaid web, and means governed by said control means for controlling therate of withdrawal of said web from its source.

9. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device having avariable web demand rate,

first means for receiving a web on one side thereof and accumulating afirst portion of said Web, second means on the other side of said firstmeans for receiving said web from said first means and accumulating asecond portion of said web, said first and second portions of said webbeing spaced in that sequence longitudinally along the web in thedirection it advances toward the utilization device, means including avacuum pump cornmunicating with said web portions for maintaining afirst and second force on said first and second portions re spectivelyof said web in a direction to oppose deplepletion of the webaccumulations, said second force being greater than said first force,said first force serving to withdraw the web from the source thereof,whereby on the occurrence of an increase in the demand rate of saidutilization device the first accumulated web portion is depleted beforethe start of depletion of the second accumulated web portion, controlmeans responsive to said first accumulated web portion, means governedby said control means for normally retarding withdrawal of the web fromits source while the web is moving under the influence of said firstforce from its source to said first means, said control means inresponse to depletion of said first accumulated web portion causing saidmeans governed thereby to reduce its retarding effect upon thewithdrawal of the web from its source, and accelerating means adapted tobe energized upon start up of the utilization device and foraccelerating withdrawal of the web from its source, said control meansupon restoration of said first accumulated web portion being adapted todeenergize said accelerator means.

10. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming first and second compartmentseach.-

adentesi tn receive rsanestivl r a a d s c d web accumulation with thecross-sectional area of the accumulation in said second compartmentbeing greater than that of the aflcumulation in said first compartment,perforate web guide members supported in said compartments, vacuum pumpmeans communicating with each of said comparunents on one side of saidweb through said guide members for maintaining an air pressuredifferential across each of said accumulations and thereby create forcesurging said web into said compartments toward said guide members formaintaining said accumulations with the force acting on said secondaccumulation greater than that acting on said first accumulation, a rollon the infced side of said first compartment, means adapted for responseto the speed of operation of said utilization device for continuouslydriving said roll, the force acting on said first accumulationmaintaining said web taut against said roll and serving to withdraw theweb from its source, control means resppnsive to depletion of said firstaccumulation and withdrawal of said web away from said guide member insaid first compartment, means governed by said control means fornormally retarding withdrawal of the web from its source while the webcontinues to move from its source to said first means, said controlmeans in resppnse to depletion of said first accumulation causing saidgoverned means to reduce its retarding eflect upon the withdrawal of theweb from its source, accelerator means for accelerating withdrawal ofthe web from its source, and means controlling energization of saidaccelerator means, said control means upon restoration of said firstaccumulation being adapted to deenergize said accelerator means.

11. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming a compartment, meanscommunicating with said compartment for maintaining an air pressuredifierent-ial across said web to thereby apply a force to said web andwithdraw it from the source thereof and maintain a web accumulation insaid compartment, control means responsive to the accumulation of Web insaid compartment, means governed by said control means for normallyretarding withdrawal of the web from its source while the web is movingunder the influence of said force from its source to said compartment,said control means in response to depletion of the accumulation of theweb causing said means governed thereby to reduce its retarding effectupon the withdrawal of the Web from its source, accelerator means foraccelerating withdrawal of the web from its source, and meanscontrolling energization of said accelerator means, said contIOl meansupon restoration of the web accumulation being adapted to deenergizesaid accelerator means.

12. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming a compartment, 21 roll on theinfeed side of Said compartment, means for continuously rotating saidroll at a speed having a predetermined relation t9 the speed ofoperation of the utilization device and which is greater than the webdemand rate of said gmi! zation device, means communicating with saidcompactment for maintaining an air pressure differential across said webto thereby apply a force to said web and withdraw it from the sourcethereof and maintain a web accumulation in said compartment, said forcemaintaining said web taut against and in sliding engagement with saidroll, control means responsive to the accumulation of web in saidcompartment, and means governed by said control means for normallyretarding withdrawal of the moving Web from its source, said controlmeans in response to depletion of the accumulation of the web causingsaid means governed thereby to reduce its retarding effect upon thewithdrawal of the web from its source.

13. In an apparatus for supplying continuous web under substantiallyuniform tension from a source thereof to a utilization device, meansdefining a path for said web and forming first and second compartmentseach adapted to receive respectively a first and second web accumulationwith the cross-sectional area of the accumulation in said secondcompartment being greater than that of the accumulation in said firstcompartment, perforate web guide members supported in said compartments,vacuum pump means communicating with each of said compartments on oneside of said web through said guide members for maintaining an airpressure differential across each of said accumulations and therebycreate forces urging said web into said compartments toward said guidemembers for maintaining said accumulations with the force acting on saidsecond accumulation greater than that acting on said first accumulation,a roll on the infeed side of said first compartment, means adapted forresponse to the speed of operation of said utilization device forcontinuously driving said roll at a peripheral speed greater than theweb demand rate of said utilization device, the force acting on saidfirst accumulation maintaining said web taut against and in slidingengagement with said roll and serving to withdraw the web from itssource, control means responsive to depletion of said first accumulationand withdrawal of said web away from said guide member in said firstcompartment, means governed by said control means for normally retardingwithdrawal of the web from its source while the web continues to movefrom its source to the first said means, said control means in responseto depletion of said first accumulation causing said governed means toreduce its retarding effect upon the withdrawal of the web from itssource, accelerator means for accelerating withdrawal of the web fromits source, and means controlling energization of said acceleratormeans, said control means upon restoration of said first accumulationbeing adapted to deenergize said accelerator means.

References Cited in the file of this patent UNITED STATES PATENTS2,147,421 Bendz Feb. 14, 1939 2,831,678 MacNeill Apr. 22, 1958 FOREIGNPATENTS 480,223 Canada Ian. 15, 1952

